Climate Data Consistent And Telling

In reply to Jim Macdonald's Jan. 27 letter, "Says Climate Data Distorted," I found nothing to support his assertion "that the data used to make that graph has been homogenized, changed and manipulated so many times it bears no resemblance to when it was first reported or to the raw surface temperature data."

I hold a doctorate degree in organic chemistry and have been giving seminars on climate change since 2012. The only thing remarkable in the latest NASA graph in question is that 2015 stands out like a sore thumb as the warmest year on record. Otherwise, the graph remains much the same as other graphs previously published by the Climatic Research Unit of the University of East Anglia (UK) and the Japanese Meteorological Agency.

The graph shows that the global mean surface temperature increased by more than 1.05 degrees Celsius since record-keeping was established in 1880. If we divide the 140-year period from 1875 to 2015 into 7 periods of 20 years each, there was only one period, 1895-1915, when the temperature went downward. There were two periods, 1875-1895, and 1955-1975, when the temperature went sideways. All the other four periods, 1915-1935, 1935-1955, 1975-1995, 1995-2015, the temperature went upward, with the steepest rise experienced in the 1975-2015 period. Last year was the warmest year on record.